Implantable devices exist that electrically stimulate body tissue to treat or relieve the symptoms of a wide variety of physiological or psychological maladies. Such devices are typically part of systems that are entirely implantable within the patient or are partially implantable and partially external to the patient. Systems that are entirely implantable in the patient typically include an implantable medical device and an extension and lead or leads. In such a system, the implantable medical device, extension and lead are entirely implanted in the bodies of the patients.
A programmer is used outside the patient's body and communicates with the implantable medical device by both sending and receiving information to and from the implantable medical device. The programmer is used to interrogate the implantable medical device and set and adjust the device operation, including the parameters of the therapy, to be most effective. Some examples of the programmer may include a computer having a programming head and a printer. The programming head may be placed over the implantable medical device to interrogate and program desired device settings using telemetry. Alternatively, the communication may be through RF communication. The programming head also receives information from the implantable medical device such as the current electrical parameters or status information.
Such implantable devices are often powered by an internal battery which permits the device to function continuously over a long period of time. Often for implantable medical devices, the internal battery used to power the device's circuitry is non-rechargeable. The battery is included in the implantable device, which in turn is surgically implanted and is typically intended to be physically inaccessible. The batteries used in conjunction with the implantable medical device are not intended to and is typically not replaceable or rechargeable. As such, the operational lifetime of the device is limited to the duration of battery life which may range from approximately three (3) years to approximately eight (8) years.
It may be desirable to obtain information from the implantable medical device when it ceases to operate such as due to the power source being completely drained. Current processes rely on returned implantable medical devices to understand failure modes and causes, and also to verify non-failure. However, due to the power source of the implantable medical device being depleted, the device cannot be interrogated via telemetry. In the case of devices that have already been implanted, the current processes are limited to implantable medical devices that can be explanted. However, future devices cannot or are not intended to be explanted and as such it is impossible to retrieve any desired information. An ability to monitor the performance of implantable medical devices is required and critical to identifying any issues that require corrective action.
What is needed are methods, devices and systems to facilitate transfer of data from the powerless IMD to an external device.